Apparatus for chilling a plurality of food trays

Abstract

Chilling apparatus especially adapted for airline food tray serving carts has a small blower at one upper end of the inside of the cart which exhausts air across a pan of dry ice or other cooling material removably positioned on an upper shelf of the cart. Spacer means in the cart enclosure prevent the trays stacked therein from blocking a vertical air flow passage at each end of the cart. Thus, the chilled air is directed downwardly from the pan over the inside wall of a door on the cart. The chilled air then passes horizontally over at least a portion of the trays containing items to be chilled and is sucked upwardly along the other inside end wall of the cart to the blower inlet duct. The apparatus is very light in weight and can provide sufficiently uniform cooling to the items on each tray which must be chilled when a container on each tray is being simultaneously heated.

I claim as my invention: 
     
       1. In an apparatus for heating at least one covered container on each of a plurality of vertically stacked trays located on a plurality of shelves in a refrigerated enclosure having a door at at least one end thereof while at least one other container on each tray is chilled, the improvement comprising at least one blower element mounted inside the enclosure adjacent the end thereof which is opposite to said door and also adjacent the top wall surface of the enclosure; a removable insulated pan adapted to contain dry ice or other cooling material positioned on a shelf of said enclosure above the stacked trays, said pan having an inlet opening at one end to receive the exhaust from said blower and an exhaust opening at its other end to direct chilled air which has passed over the cooling material in the pan downwardly over the inside surface of said door; spacing means located in said enclosure and/or on the trays for spacing the trays from at least portions of said door and from at least portions of the enclosure end which is opposite to said door, and prevent them from blocking the vertical flow of chilled air passing along the portions of the inside walls of said door and opposite enclosure ends which are adjacent the portions of the trays containing the containers to be chilled, said flow of chilled air being thereby channeled so as to pass downwardly along the door adjacent the exhaust opening in said pan, horizontally across the containers to be chilled on said vertically stacked trays, and upwardly along the end wall of said enclosure opposite to said door to an inlet duct means for said at least one blower element. 
     
     
       2. The apparatus of claim 1 wherein said insulated pan has an elongated curved deflector portion at its exhaust end which is adapted to collect chilled air being blown horizontally across the cooling material in the pan and direct it downwardly. 
     
     
       3. The apparatus of claim 2 wherein the upper surface of the bottom wall of said pan is substantially free of vertical obstructions in the region of said curved deflector so that the chilled air can flow smoothly therefrom into said deflector. 
     
     
       4. The apparatus of claim 1 wherein the pan is insulated at least on its underneath surface, said insulation being substantially thicker along the portion of the pan which is adapted to overlie the containers to be heated than along the portion which overlies the containers to be chilled. 
     
     
       5. The apparatus of claim 4 wherein the bottom inside wall of the pan is deeper on the portion thereof which overlies the containers to be chilled. 
     
     
       6. The apparatus of claim 1 wherein a perforated shelf is positioned in said pan, said shelf being adapted to overlie a layer of dry ice placed on the bottom wall of the pan and to support an additional layer of dry ice.